Efforts to crack down on foreign bribery have failed to stem the practice as a proportion of global trade, despite some high-profile anti-corruption cases, according to a report by Transparency International.

Only about a quarter of the world’s exports come from countries with active law enforcement efforts against international corruption, the anti-graft group wrote in the report. While it noted improvement in eight countries, including Brazil, Israel and Italy, enforcement declined in four others.

The group also examined China, India, Hong Kong and Singapore for the first time and categorized them as doing little or nothing to stop their companies from bribing officials outside their borders.